A long time ago gravity drew two galaxies together into the gorgeously chaotic state we see above with NGC 6052. Stars from within both of the original galaxies now follow new trajectories caused by the new gravitational effects.
However, actual collisions between stars themselves are very rare as stars are very small relative to the distances of empty space between them. Eventually the galaxies will fully merge to form a single, stable galaxy. A Preview of what the Milky Way will undergo in the future with our nearest galactic neighbor, the Andromeda galaxy in around 4 billion years.
Located in the constellation of Hercules, about 230 million light-years away, NGC 6052 is a pair of colliding galaxies. They were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding. This particular image of NGC 6052 was taken using the Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope.
The Daily Galaxy, Jake Burba, via ESA/Hubble & NASA, A. Adamo et al.